Welp, that turned out to be a dud. Sure, the body, frame, engine, 12v conversion, etc. are good, but the box is ruined, hydraulic pump is toast and the real nail in the coffin: the back axle. Somehow, a previous user broke the drum and their 'fix' was to cut it off the hub. When I searched for replacement, no other truck had the same axle! Does this have some unique to the year axle or could it have been also replaced, like the engine did?
Either way, I'm no longer worried about it, has I got a similar '53 in much better condition that is mostly original. Should have it home soon and will post about it!